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    </script></div> <ul class="sidebar-links"><li><a href="/sass-cn/install/" class="sidebar-link">安装</a></li><li><section class="sidebar-group depth-0"><p class="sidebar-heading"><span>学习指南</span> <!----></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/sass-cn/learn/" class="sidebar-link">基础知识</a></li><li><a href="/sass-cn/learn/Preprocessing.html" class="sidebar-link">预处理</a></li><li><a href="/sass-cn/learn/Variables.html" class="sidebar-link">变量</a></li><li><a href="/sass-cn/learn/Nesting.html" class="sidebar-link">嵌套规则</a></li><li><a href="/sass-cn/learn/Partials.html" class="sidebar-link">片段文件</a></li><li><a href="/sass-cn/learn/Import.html" class="sidebar-link">文件导入</a></li><li><a href="/sass-cn/learn/Mixins.html" class="sidebar-link">混合器</a></li><li><a href="/sass-cn/learn/Extend.html" class="sidebar-link">扩展与继承</a></li><li><a href="/sass-cn/learn/Operators.html" class="sidebar-link">操作符</a></li></ul></section></li><li><section class="sidebar-group depth-0"><p class="sidebar-heading"><span>文档</span> <!----></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/sass-cn/api/" class="sidebar-link">综述</a></li><li><section class="sidebar-group collapsable is-sub-group depth-1"><p class="sidebar-heading"><span>语法</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable is-sub-group depth-1"><p class="sidebar-heading"><span>样式规则</span> <span class="arrow right"></span></p> <!----></section></li><li><a href="/sass-cn/api/Variables.html" class="sidebar-link">变量</a></li><li><a href="/sass-cn/api/Interpolation.html" class="sidebar-link">插值</a></li><li><section class="sidebar-group collapsable is-sub-group depth-1"><p class="sidebar-heading"><span>@规则</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable is-sub-group depth-1"><p class="sidebar-heading open"><span>值类型</span> <span class="arrow down"></span></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/sass-cn/api/Values/" class="sidebar-link">概述</a></li><li><a href="/sass-cn/api/Values/Numbers.html" class="active sidebar-link">Numbers</a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header"><a href="/sass-cn/api/Values/Numbers.html#单位" class="sidebar-link">单位</a></li><li class="sidebar-sub-header"><a href="/sass-cn/api/Values/Numbers.html#精度" class="sidebar-link">精度</a></li></ul></li><li><a href="/sass-cn/api/Values/Strings.html" class="sidebar-link">Strings</a></li><li><a href="/sass-cn/api/Values/Colors.html" class="sidebar-link">Colors</a></li><li><a href="/sass-cn/api/Values/Lists.html" class="sidebar-link">Lists</a></li><li><a href="/sass-cn/api/Values/Maps.html" class="sidebar-link">Maps</a></li><li><a href="/sass-cn/api/Values/Booleans.html" class="sidebar-link">Booleans</a></li><li><a href="/sass-cn/api/Values/Null.html" class="sidebar-link">Null</a></li><li><a href="/sass-cn/api/Values/Functions.html" class="sidebar-link">Functions</a></li></ul></section></li><li><section class="sidebar-group collapsable is-sub-group depth-1"><p class="sidebar-heading"><span>操作符</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable is-sub-group depth-1"><p class="sidebar-heading"><span>内置模块</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable is-sub-group depth-1"><p class="sidebar-heading"><span>重大改变</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable is-sub-group depth-1"><p class="sidebar-heading"><span>命令行</span> <span class="arrow right"></span></p> <!----></section></li><li><a href="/sass-cn/api/JsApi.html" class="sidebar-link">JavaScript API</a></li></ul></section></li></ul> </aside> <main class="page"> <div class="theme-default-content content__default"><h1 id="numbers"><a href="#numbers" aria-hidden="true" class="header-anchor">#</a> Numbers</h1> <div><script async="async" src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script> <ins data-ad-client="ca-pub-6227283216337087" data-ad-slot="9720145993" class="adsbygoogle" style="display:inline-block;width:600px;height:90px"></ins> <script>
    (adsbygoogle = window.adsbygoogle || []).push({});
    </script></div> <p>Sass中的数字有两个组成部分：数字本身和它的单位。例如，在<code>16px</code>中，数字是<code>16</code>，单位是<code>px</code>。数字可以没有单位，也可以有复杂的单位。查看<a href="/sass-cn/api/Values/Numbers.html#单位">单位</a>的更多细节。</p> <div class="el-tabs el-tabs--top el-tabs--border-card"><div class="el-tabs__header is-top"><div class="el-tabs__nav-wrap is-top"><div class="el-tabs__nav-scroll"><div role="tablist" class="el-tabs__nav is-top" style="transform:translateX(-0px);"></div></div></div></div><div class="el-tabs__content"><div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-scss extra-class"><pre class="language-scss"><code><span class="token keyword">@debug</span> 100<span class="token punctuation">;</span> <span class="token comment">// 100</span>
<span class="token keyword">@debug</span> 0.8<span class="token punctuation">;</span> <span class="token comment">// 0.8</span>
<span class="token keyword">@debug</span> 16px<span class="token punctuation">;</span> <span class="token comment">// 16px</span>
<span class="token keyword">@debug</span> 5px <span class="token operator">*</span> 2px<span class="token punctuation">;</span> <span class="token comment">// 10px*px (read &quot;square pixels&quot;)</span>
</code></pre></div></div> <div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-sass extra-class"><pre class="language-sass"><code><span class="token atrule-line"><span class="token atrule">@debug</span> 100  // 100</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 0.8  // 0.8</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 16px  // 16px</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 5px * 2px  // 10px*px (read &quot;square pixels&quot;)</span>
</code></pre></div></div></div></div> <p>Sass数字支持与CSS数字相同的格式，包括<a href="https://zh.wikipedia.org/wiki/%E8%AE%A1%E9%87%8F%E5%8D%95%E4%BD%8D" target="_blank" rel="noopener noreferrer">科学表示法<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a>，该表示法的<code>e</code>值介于数字和10的幂之间。由于历史上浏览器对科学符号的支持一直参差不齐，所以Sass总是将其编译为完全展开的数字。</p> <div class="el-tabs el-tabs--top el-tabs--border-card"><div class="el-tabs__header is-top"><div class="el-tabs__nav-wrap is-top"><div class="el-tabs__nav-scroll"><div role="tablist" class="el-tabs__nav is-top" style="transform:translateX(-0px);"></div></div></div></div><div class="el-tabs__content"><div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-scss extra-class"><pre class="language-scss"><code><span class="token keyword">@debug</span> 5.2e3<span class="token punctuation">;</span> <span class="token comment">// 5200</span>
<span class="token keyword">@debug</span> 6e-2<span class="token punctuation">;</span> <span class="token comment">// 0.06</span>
</code></pre></div></div> <div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-sass extra-class"><pre class="language-sass"><code><span class="token atrule-line"><span class="token atrule">@debug</span> 5.2e3  // 5200</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 6e-2  // 0.06</span>
</code></pre></div></div></div></div> <div class="warning custom-block"><p>Sass不区分整数和小数，例如<code>5/2</code>返回<code>2.5</code>而不是<code>2</code>。这与JavaScript的行为相同，但与许多其他编程语言不同。</p></div> <h2 id="单位"><a href="#单位" aria-hidden="true" class="header-anchor">#</a> 单位</h2> <p>Sass对操作基于<a href="https://zh.wikipedia.org/wiki/%E8%AE%A1%E9%87%8F%E5%8D%95%E4%BD%8D" target="_blank" rel="noopener noreferrer">计量单位<svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg></a>的单位计算提供了强大的支持。当两个数相乘时，它们的单位也相乘。当一个数除以另一个数时，结果取第一个数的分子单位和第二个数的分母单位。一个数在分子和/或分母上可以有任意数量的单位。</p> <div class="el-tabs el-tabs--top el-tabs--border-card"><div class="el-tabs__header is-top"><div class="el-tabs__nav-wrap is-top"><div class="el-tabs__nav-scroll"><div role="tablist" class="el-tabs__nav is-top" style="transform:translateX(-0px);"></div></div></div></div><div class="el-tabs__content"><div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-scss extra-class"><pre class="language-scss"><code><span class="token keyword">@debug</span> 4px <span class="token operator">*</span> 6px<span class="token punctuation">;</span> <span class="token comment">// 24px*px (read &quot;square pixels&quot;)</span>
<span class="token keyword">@debug</span> 5px <span class="token operator">/</span> 2s<span class="token punctuation">;</span> <span class="token comment">// 2.5px/s (read &quot;pixels per second&quot;)</span>
<span class="token keyword">@debug</span> 5px <span class="token operator">*</span> 30deg <span class="token operator">/</span> 2s <span class="token operator">/</span> 24em<span class="token punctuation">;</span> <span class="token comment">// 3.125px*deg/s*em</span>
                                <span class="token comment">// (read &quot;pixel-degrees per second-em&quot;)</span>

<span class="token property"><span class="token variable">$degrees-per-second</span></span><span class="token punctuation">:</span> 20deg/1s<span class="token punctuation">;</span>
<span class="token keyword">@debug</span> <span class="token variable">$degrees-per-second</span><span class="token punctuation">;</span> <span class="token comment">// 20deg/s</span>
<span class="token keyword">@debug</span> 1 <span class="token operator">/</span> <span class="token variable">$degrees-per-second</span><span class="token punctuation">;</span> <span class="token comment">// 0.05s/deg</span>
</code></pre></div></div> <div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-sass extra-class"><pre class="language-sass"><code><span class="token atrule-line"><span class="token atrule">@debug</span> 4px * 6px  // 24px*px (read &quot;square pixels&quot;)</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 5px / 2s  // 2.5px/s (read &quot;pixels per second&quot;)</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 5px * 30deg / 2s / 24em  // 3.125px*deg/s*em</span>
<span class="token comment">//                                 (read &quot;pixel-degrees per second-em&quot;)</span>

<span class="token variable-line"><span class="token variable">$degrees-per-second</span><span class="token punctuation">:</span> 20deg<span class="token operator">/</span>1s</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> $degrees-per-second  // 20deg/s</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 1 / $degrees-per-second  // 0.05s/deg</span>
</code></pre></div></div></div></div> <div class="warning custom-block"><p>因为CSS不支持像素*像素这样的复杂单位，所以使用带有复杂单位的数字作为<a href="/sass-cn/api/StyleRules/PropertyDeclarations.html">属性值</a>会产生错误。不过，这是一个伪装的特性；如果你没有得到正确的单位，这通常意味着你的计算出了问题！记住，您可以使用<a href="/sass-cn/api/AtRules/Debug.html">@debug规则</a>来检查任何变量或<a href="/sass-cn/api/Syntax/Structure.html#表达式">表达式</a>的单位。</p></div> <p>Sass将自动兼容不同单位类型间的转换，尽管它将为结果选择哪个单元取决于使用的是哪种Sass实现。如果您试图组合不兼容的单元，比如<code>1in + 1em</code>， Sass将抛出会抛错。</p> <div class="el-tabs el-tabs--top el-tabs--border-card"><div class="el-tabs__header is-top"><div class="el-tabs__nav-wrap is-top"><div class="el-tabs__nav-scroll"><div role="tablist" class="el-tabs__nav is-top" style="transform:translateX(-0px);"></div></div></div></div><div class="el-tabs__content"><div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-scss extra-class"><pre class="language-scss"><code><span class="token comment">// CSS defines one inch as 96 pixels.</span>
<span class="token keyword">@debug</span> 1in <span class="token operator">+</span> 6px<span class="token punctuation">;</span> <span class="token comment">// 102px or 1.0625in</span>

<span class="token keyword">@debug</span> 1in <span class="token operator">+</span> 1s<span class="token punctuation">;</span>
<span class="token comment">//     ^^^^^^^^</span>
<span class="token comment">// Error: Incompatible units s and in.</span>
</code></pre></div></div> <div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-sass extra-class"><pre class="language-sass"><code><span class="token comment">// CSS defines one inch as 96 pixels.</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 1in <span class="token atrule">+</span> 6px  // 102px or 1.0625in</span>

<span class="token atrule-line"><span class="token atrule">@debug</span> 1in <span class="token atrule">+</span> 1s</span>
<span class="token comment">//     ^^^^^^^^</span>
<span class="token comment">// Error: Incompatible units s and in.</span>
</code></pre></div></div></div></div> <p>在实际的单位计算中，如果分子中包含的单位与分母中的单位（比如<code>96px / 1in</code>）相匹配，那么它们就会相互抵消。这样就很容易定义一个比率，您可以使用它在单位之间进行转换。在下面的示例中，我们将所需的速度设置为每50个像素1秒，然后将其乘以transition覆盖的像素数，以获得所需的时间。</p> <div class="el-tabs el-tabs--top el-tabs--border-card"><div class="el-tabs__header is-top"><div class="el-tabs__nav-wrap is-top"><div class="el-tabs__nav-scroll"><div role="tablist" class="el-tabs__nav is-top" style="transform:translateX(-0px);"></div></div></div></div><div class="el-tabs__content"><div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-scss extra-class"><pre class="language-scss"><code><span class="token property"><span class="token variable">$transition-speed</span></span><span class="token punctuation">:</span> 1s/50px<span class="token punctuation">;</span>

<span class="token keyword">@mixin</span> <span class="token function">move</span><span class="token punctuation">(</span><span class="token variable">$left-start</span><span class="token punctuation">,</span> <span class="token variable">$left-stop</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
  <span class="token property">position</span><span class="token punctuation">:</span> absolute<span class="token punctuation">;</span>
  <span class="token property">left</span><span class="token punctuation">:</span> <span class="token variable">$left-start</span><span class="token punctuation">;</span>
  <span class="token property">transition</span><span class="token punctuation">:</span> left <span class="token punctuation">(</span><span class="token variable">$left-stop</span> <span class="token operator">-</span> <span class="token variable">$left-start</span><span class="token punctuation">)</span> <span class="token operator">*</span> <span class="token variable">$transition-speed</span><span class="token punctuation">;</span>

  <span class="token selector"><span class="token parent important">&amp;</span>:hover </span><span class="token punctuation">{</span>
    <span class="token property">left</span><span class="token punctuation">:</span> <span class="token variable">$left-stop</span><span class="token punctuation">;</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

<span class="token selector">.slider </span><span class="token punctuation">{</span>
  <span class="token keyword">@include</span> <span class="token function">move</span><span class="token punctuation">(</span>10px<span class="token punctuation">,</span> 120px<span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div></div> <div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-sass extra-class"><pre class="language-sass"><code><span class="token variable-line"><span class="token variable">$transition-speed</span><span class="token punctuation">:</span> 1s<span class="token operator">/</span>50px</span>

<span class="token atrule-line"><span class="token atrule">@mixin</span> move($left-start, $left-stop)</span>
<span class="token property-line">  <span class="token property">position</span><span class="token punctuation">:</span> absolute</span>
<span class="token property-line">  <span class="token property">left</span><span class="token punctuation">:</span> <span class="token variable">$left-start</span></span>
<span class="token property-line">  <span class="token property">transition</span><span class="token punctuation">:</span> left (<span class="token variable">$left-stop</span> <span class="token operator">-</span> <span class="token variable">$left-start</span>) <span class="token operator">*</span> <span class="token variable">$transition-speed</span></span>

<span class="token property-line">  <span class="token property">&amp;</span><span class="token punctuation">:</span><span class="token property">hover</span></span>
<span class="token property-line">    <span class="token property">left</span><span class="token punctuation">:</span> <span class="token variable">$left-stop</span></span>

<span class="token selector">.slider</span>
<span class="token atrule-line">  <span class="token atrule">@include</span> move(10px, 120px)</span>
</code></pre></div></div> <div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-css extra-class"><pre class="language-css"><code><span class="token selector">.slider</span> <span class="token punctuation">{</span>
  <span class="token property">position</span><span class="token punctuation">:</span> absolute<span class="token punctuation">;</span>
  <span class="token property">left</span><span class="token punctuation">:</span> 10px<span class="token punctuation">;</span>
  <span class="token property">transition</span><span class="token punctuation">:</span> left 2.2s<span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token selector">.slider:hover</span> <span class="token punctuation">{</span>
  <span class="token property">left</span><span class="token punctuation">:</span> 120px<span class="token punctuation">;</span>
<span class="token punctuation">}</span>
</code></pre></div></div></div></div> <div class="warning custom-block"><p>在实际的单位计算中，如果分子中包含的单位与分母中的单位(比如96px / 1in)相匹配，那么它们就会相互抵消。这样就很容易定义一个比率，您可以使用它在单位之间进行转换。在下面的示例中，我们将所需的速度设置为每50个像素1秒，然后将其乘以转换覆盖的像素数，以获得所需的时间。</p> <p>您应该特别避免使用像<code>#{$number}px</code>这样的内插。这实际上并没有创建一个数字！它创建了一个看起来像数字的<a href="%E5%BE%85%E7%A1%AE%E5%AE%9A">无引号字符串</a>，不能用于任何<a href="%E5%BE%85%E7%A1%AE%E5%AE%9A">数字操作</a>或<a href="">函数</a>。试着把你的数字单位提取出来，这样<code>$number</code>就已经有了单位<code>px</code>，或者写成<code>$number * 1px</code>。</p></div> <div class="warning custom-block"><p>Sass中的百分比和其他单位一样有效。它们不能与小数互换，因为在CSS中小数和百分数的含义不同。例如，<code>50%</code>是一个以<code>%</code>为单位的数字，Sass认为它与<code>0.5</code>不同。</p> <p>可以使用单位算术在小数和百分数之间进行转换。<code>$percentage / 100%</code>将返回对应的小数，<code>$decimal * 100%</code>将返回对应的百分比。还可以使用<a href="%E5%BE%85%E7%A1%AE%E5%AE%9A">percent()</a>作为更显式的<code>$decimal * 100%</code>的写法。</p></div> <h2 id="精度"><a href="#精度" aria-hidden="true" class="header-anchor">#</a> 精度</h2> <p>兼容性：Dart Sass ✓ <span class="sa-ver-divider">|</span>LibSass  ✗<span class="sa-ver-divider">|</span>Ruby Sass  <span class="badge tip" style="vertical-align:middle;" data-v-0f036736>3.5.0+</span></p> <blockquote><p>LibSass和旧版本的Ruby Sass默认为5位数字精度，但是可以配置为使用不同的数字。建议用户将它们配置为10位，以获得更高的精度和向前兼容性。</p></blockquote> <p>Sass数字支持小数点后最多10位的精度。这意味着一些不同的事情：</p> <ul><li>生成的CSS中只包含小数点后数字的前十位。</li> <li>如果小数点后10位之前是相同的，像<code>==</code>和<code>&gt;=</code>这样的操作会认为两个数字是等价的。</li> <li>如果一个数字与一个整数的距离小于<code>0.0000000001</code>，那么对于像<a href="%E5%BE%85%E7%A1%AE%E5%AE%9A">nth()</a>这样需要整数参数的函数来说，它就是一个整数。</li></ul> <div class="el-tabs el-tabs--top el-tabs--border-card"><div class="el-tabs__header is-top"><div class="el-tabs__nav-wrap is-top"><div class="el-tabs__nav-scroll"><div role="tablist" class="el-tabs__nav is-top" style="transform:translateX(-0px);"></div></div></div></div><div class="el-tabs__content"><div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-scss extra-class"><pre class="language-scss"><code><span class="token keyword">@debug</span> 0.012345678912345<span class="token punctuation">;</span> <span class="token comment">// 0.0123456789</span>
<span class="token keyword">@debug</span> 0.01234567891 <span class="token operator">==</span> 0.01234567899<span class="token punctuation">;</span> <span class="token comment">// true</span>
<span class="token keyword">@debug</span> 1.00000000009<span class="token punctuation">;</span> <span class="token comment">// 1</span>
<span class="token keyword">@debug</span> 0.99999999991<span class="token punctuation">;</span> <span class="token comment">// 1</span>
</code></pre></div></div> <div role="tabpanel" aria-hidden="true" id="pane-null" aria-labelledby="tab-null" class="el-tab-pane" style="display:none;"><div class="language-sass extra-class"><pre class="language-sass"><code><span class="token atrule-line"><span class="token atrule">@debug</span> 0.012345678912345  // 0.0123456789</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 0.01234567891 <span class="token atrule">=</span><span class="token atrule">=</span> 0.01234567899  // true</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 1.00000000009  // 1</span>
<span class="token atrule-line"><span class="token atrule">@debug</span> 0.99999999991  // 1</span>
</code></pre></div></div></div></div> <div class="tip custom-block"><p>当数字在与精度相关的地方使用时，它们会<strong>延迟</strong>四舍五入到精度为10位的数字。这意味着数学函数将在内部处理完整的数值，以避免积累额外的舍入错误。</p></div></div> <footer class="page-edit"><!----> <div class="last-updated"><span class="prefix">上次更新: </span> <span class="time">11/5/2019, 4:49:11 PM</span></div></footer> <div class="page-nav"><p class="inner"><span class="prev">
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